Incremental Value of the En Face View of the Tricuspid Valve by Two-Dimensional and Three-Dimensional Echocardiography for Accurate Identification of Tricuspid Valve Leaflets

Background: In this study, advanced postprocessing of three-dimensional echocardiographic (3DE) data sets was used to identify tricuspid valve (TV) leaflets in two-dimensional echocardiographic (2DE) views, and the feasibility of the subcostal view to obtain 2DE en face views of the TV, as an alternative imaging option to image reconstruction from 3DE imaging, was also tested. Methods: In 155 consecutive patients, attempts were made to obtain the en face view of the TV by 2DE imaging (from the subcostal window) and by reconstruction from 3DE imaging. Using both in-housedeveloped and commercially available software for postprocessing of 3DE data, image planes from the standard 2DE views were reconstructed and TV leaflets identified in each view. Results: With 2DE imaging, all TV leaflets could be visualized in 58% of patients, compared with 56% using 3DE imaging. In 30 patients (19%), en face views of the TV could be obtained only by 3DE imaging. The anterior leaflet was the largest one in 90% of patients, and the smallest leaflet was either the posterior (49%) or septal (41%) leaflet. In 12% of patients, the TV was either bicuspid or quadricuspid. In patients with pacemakers, the position of the right ventricular lead relative to the TV leaflets was readily determined using both imaging techniques. Visible TV leaflets varied in all standard 2DE views because of variability in image planes and leaflet morphology. Conclusions: High variability in TV leaflet anatomy and the dependence on transducer position do not allow schematic leaflet identification. All existing TV leaflet identification schemes are therefore only partially correct, and if correct leaflet identification is needed, the use of an en face view is recommended.